Heather Raphael is fourteen and attends Ripley Collegiate School for Girls which she very much enjoys but her father is concerned about standards at the school and about the effect it is having on his daughter, while her mother is afraid that Heather is forgetting that she is 'supposed to be a gentlewoman'. So Major Raphael decrees that Heather shall leave at the end of term and come home to have lessons from a governess, Miss Christopher, who will also teach her two sisters and the four daughters of the local Vicar.
Heather is not happy about this and sulks for quite a time, not believing that her parents are taking this action because it is best for her. Several of her friends are also being taken away from Ripley (oddly they all seem to get letters from home about this on the same day!) and this forces the Head to make changes although not quickly enough to stop these girls leaving.
After a bad tempered journey home, Heather's mood improves when her sisters, Hazel and Honey, are so pleased to see her. The next day the family departs for a long summer holiday in Guernsey. On the boat Heather meets Janie Temple and Pauline Ozanne and they quickly make friends. The families become close over the summer. Janie helps Heather to see that her attitude will not help change her father's mind and she becomes resigned to not going back to Ripley.
Back at home the Raphaels are joined by the Shakespeare girls for lessons. Heather and Cressida, the eldest, do not get along. Cressie is inclined to be a prig and look down on Heather. She also acts older than her age as she has effectively been the mother of the family for many years.
After adventures involving secret passages, mummers plays, villains and a visit from Janie and Pauline, Heather becomes the type of girl her parents want her to be, makes friends with Cressie and finds that in the next year her life will change yet again - but this time in a way she is much happier about.
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